939 resultados para Repertoire


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The contribution of recent thymic emigrants (RTEs) to the peripheral naïve T cell population is necessary to maintain diversity of the T cell receptor (TCR) repertoire and produce immune responses against newly encountered antigens. The thymus involutes with age, after irradiation or chemotherapy, and due to severe viral infections. Thymus involution results in decreased thymopoiesis and RTE output leading to a reduced diversity of peripheral T cells. This increases susceptibility to disease and impairs immune responsiveness to vaccines. Therefore, studies aimed at maintaining or regenerating thymic function are integral for maintaining and restoring peripheral TCR diversity. Mice that express a K5.CyclinD1 transgene expression have a severely hyperplastic thymus that fails to undergo involution. Both thymocyte and TEC development appear normal in these mice. We have used the K5.CyclinD1 transgenic model to test the hypothesis that preventing thymus involution will sustain RTE output and incorporation into the peripheral T cell pool to prevent naïve T cell depletion with age. The K5.CyclinD1 transgene was crossed to the RAG2p-GFP transgenic model so that RTEs could be tracked by the intensity of the GFP signal. The frequency and number of RTEs in naïve CD4 splenic T cells was analyzed at monthly intervals to 5 months of age. Using this double transgenic approach, we determined that preventing thymus involution does maintain or enhance the number of RTEs in the peripheral T cell pool before and after thymus involution.

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Prenatal diagnosis is traditionally made via invasive procedures such as amniocentesis and chorionic villus sampling (CVS). However, both procedures carry a risk of complications, including miscarriage. Many groups have spent years searching for a way to diagnose a chromosome aneuploidy without putting the fetus or the mother at risk for complications. Non-invasive prenatal testing (NIPT) for chromosome aneuploidy became commercially available in the fall of 2011, with detection rates similar to those of invasive procedures for the common autosomal aneuploidies (Palomaki et al., 2011; Ashoor et al. 2012; Bianchi et al. 2012). Eventually NIPT may become the diagnostic standard of care and reduce invasive procedure-related losses (Palomaki et al., 2011). The integration of NIPT into clinical practice has potential to revolutionize prenatal diagnosis; however, it also raises some crucial issues for practitioners. Now that the test is clinically available, no studies have looked at the physicians that will be ordering the testing or referring patients to practitioners who do. This study aimed to evaluate the attitudes of OB/GYN’s and how they are incorporating the test into clinical practice. Our study shows that most physicians are offering this new, non-invasive technology to their patients, and that their practices were congruent with the literature and available professional society opinions. Those physicians who do not offer NIPT to their patients would like more literature on the topic as well as instructive guidelines from their professional societies. Additionally, this study shows that the practices and attitudes of MFMs and OBs differ. Our population feels that the incorporation of NIPT will change their practices by lowering the amount of invasive procedures, possibly replacing maternal serum screening, and that it will simplify prenatal diagnosis. However, those physicians who do not offer NIPT to their patients are not quite sure how the test will affect their clinical practice. From this study we are able to glean how physicians are incorporating this new technology into their practice and how they feel about the addition to their repertoire of tests. This knowledge gives insight as to how to best move forward with the quickly changing field of prenatal diagnosis.

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Hemophilia A is a clotting disorder caused by functional factor VIII (FVIII) deficiency. About 25% of patients treated with therapeutic recombinant FVIII develop antibodies (inhibitors) that render subsequent FVIII treatments ineffective. The immune mechanisms of inhibitor formation are not entirely understood, but circumstantial evidence indicates a role for increased inflammatory response, possibly via stimulation of Toll-like receptors (TLRs), at the time of FVIII immunization. I hypothesized that stimulation through TLR4 in conjunction with FVIII treatments would increase the formation of FVIII inhibitors. To test this hypothesis, FVIII K.O. mice were injected with recombinant human FVIII with or without concomitant doses of TLR4 agonist (lipopoysaccharide; LPS). The addition of LPS combined with FVIII significantly increased the rate and the production of anti-FVIII IgG antibodies and neutralizing FVIII inhibitors. In the spleen, repeated in vivo TLR4 stimulation with LPS increased the relative percentage of macrophages and dendritic cells (DCs) over the course of 4 injections. However, repeated in vivo FVIII stimulation significantly increased the density of TLR4 expressed on the surface of all spleen antigen presenting cells (APCs). Culture of splenocytes isolated from mice revealed that the combined stimulation of LPS and FVIII also synergistically increased early secretion of the inflammatory cytokines IL-6, TNF-α, and IL-10, which was not maintained throughout the course of the repeated injections. While cytokine secretion was relatively unchanged in response to FVIII re-stimulation in culture, LPS re-stimulation in culture induced increased and prolonged inflammatory cytokine secretion. Re-stimulation with both LPS and FVIII induced cytokine secretion similar to LPS stimulation alone. Interestingly, long term treatment of mice with LPS alone resulted in splenocytes that showed reduced response to FVIII in culture. Together these results indicated that creating a pro-inflammatory environment through the combined stimulation of chronic, low-dose LPS and FVIII changed not only the populations but also the repertoire of APCs in the spleen, triggering the increased production of FVIII inhibitors. These results suggested an anti-inflammatory regimen should be instituted for all hemophilia A patients to reduce or delay the formation of FVIII inhibitors during replacement therapy.

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Cell-based therapies have demonstrated potency and efficacy as cancer treatment modalities. T cells can be dichotomized by their T cell receptor (TCR) complexes where alpha/beta T cells (95% of T cells) and gamma/delta T cells (+T cells proliferated to clinically significant numbers and ROR1+ tumor cells were effectively targeted and killed by both ROR1-specific CAR+ T cell populations, although ROR1RCD137 were superior to ROR1RCD28 in clearance of leukemia xenografts in vivo. The second specific aim focused on generating bi-specific CD19-specific CAR+ gamma/delta T cells with polyclonal TCRgamma/delta repertoire on CD19+ artificial antigen presenting cells (aAPC). Enhanced cytolysis of CD19+ leukemia was observed by CAR+ gamma/delta T cells compared to CARneg gamma/delta T cells, and leukemia xenografts were significantly reduced compared to control mice in vivo. The third specific aim looked at the broad anti-tumor effects of polyclonal gamma/delta T cells expanded on aAPC without CAR+ T cells, where Vdelta1, Vdelta2, and Vdelta3 populations had naïve, effector memory, and central memory phenotypes and effector function strength in the following order: Vdelta2>Vdelta3>Vdelta1. Polyclonal gamma/delta T cells eliminated ovarian cancer xenografts in vivo and increased survival compared to control mice. Thus, translating these methodologies to clinical trials will provide cancer patients novel, safe, and effective options for their treatment.

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Multiple sclerosis (MS) is the most common autoimmune disease of the central nerve system and Guillain Barré Syndrome (GBS) is an inflammatory neuropathy involving the peripheral nerves. Anti-myelin immunoglobins may play a role in the demyelination processes of the both diseases. Sulfatide is an abundant glycolipid on myelin and is a candidate target antigen for disease related autoantibodies. The objective of this study was to characterize anti-sulfatide antibodies and compare antibodies from GBS and MS patients with fetal antibodies. Our hypothesis is that some B cells producing disease-associated autoantibodies are derived from or related to B cells of the fetal repertoire. Here we report that reactivity of plasma IgM against sulfatide was elevated in twelve MS patients compared with twelve normal subjects. This result implies that anti-sulfatide antibodies are disease-related. A total of sixteen human B lymphocyte clones producing anti-sulfatide autoantibodies were isolated from MS patients, GBS patients and a human fetus. Seven of the clones were from three MS patients, four of the clones were from three GBS patients and five were from the spleen of a twenty-week human fetus. Sequences have been obtained for the heavy and light chain variable regions (VDJ and VJ regions) of all of the anti-sulfatide immunoglobulins. Seven of the sixteen antibodies used VH3 for the variable region gene of the heavy chain consistent with the rate of VH3 usage in randomly selected B cells. Somatic mutations were significantly more frequent in the patient antibodies than in the fetus and somatic mutations in CDR's (Complementarity Determining Region) were significantly more frequent than in framework regions. No significant difference was found between patients and fetus in length of VH CDRIII. However, it is reported that antibodies from randomly selected normal adult B cells have longer CDRIII lengths than those of the fetus (Sanz I, 1991 Journal of Immunology Sep 1;147(5):1720-9). Our results are consistent with derivation of the precursors of B cells producing these autoantibodies from B cells related to those of the fetal repertoire. These findings are consistent with a model in which quiescent B cells from clones produced early in development undergo proliferation in dysregulated disease states, accumulating somatic mutations and increasing in reactivity toward self-antigens. ^ Epitope mapping and molecular modeling were done to elucidate the relationships between antibody structure and binding characteristics. The autoantibodies were tested for binding activity to three different antigens: sulfatide, galactoceramide and ceramide. Molecular modeling suggests that antibodies with positive charge surrounded by or adjacent to hydrophobic groups in the binding pocket bind to the head of sulfatide via the sulfate group through electrostatic interactions. However, the antibodies with hydrophobic groups separated from positive charges appear to bind to the hydrophobic tail of sulfatide. This observation was supported by a study of the effect of NaCl concentration on antigen binding. The result suggested that electrostatic interactions played a major role in sulfate group binding and that hydrophobic interactions were of greater importance for binding to the ceramide group. Our three-dimensional structure data indicated that epitope specificity of these antibodies is more predictable at the level of tertiary than primary structure and suggested positive selection based on structure occurred in the. formation of those autoantibodies. ^

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Desde Eurípides y Séneca, sin olvidar a Racine y Garnier, el mito de Fedra ejerció una especial atracción sobre el arte, y su vigencia se ha visto renovada periódicamente. La poética de grandes sectores artísticos de finales del siglo XIX, articulada por la remisión al código clasicista y por el apartamiento de toda forma de arte vulgar o burgués, produjo una de las últimas versiones de la tragedia: la Fedra (1909) de Gabriele d’Annunzio. En este trabajo, voy a detenerme en algunas claves culturales del texto del dramaturgo italiano. En ellas se refleja una lectura del mito antiguo en clave nietzscheana, en virtud de la inclusión de dos personajes agregados por D’Annunzio al repertorio clásico.

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Dentro de las composiciones de extracción oral y popular se destaca la utilización de algunas palabras que entrañan una enorme significación. Se trata de estribillos que funcionan como una especie de muletilla expresiva, rítmica y metafórica, aunque el sentido oculto al que remiten resulte un tanto misterioso. Estos artilugios estilísticos, a mitad de camino entre la onomatopeya, el juego de palabras e ironías y el comodín rítmico y métrico, contienen muchas veces, un doble sentido insinuante que conlleva denotaciones pícaras y sensuales, atrevidas, procaces y a veces escandalosas. Este repertorio poético, antes desatendido, persiste no como reflejo pasivo de tradiciones heredadas, sino como crisol vivo de nuevas recreaciones y reconfiguraciones que impregnan géneros, repertorios y diversos registros

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Este artículo analiza el proceso de incorporación de los sectores de la Tendencia Revolucionaria del Peronismo en el gobierno de Oscar Bidegain en la provincia de Buenos Aires, a partir de las elecciones del 11 de marzo de 1973. Se busca analizar tanto la trayectoria previa de los grupos que integraron la administración provincial, sus lugares específicos en el organigrama gubernamental, junto con las expectativas, los sentidos y los objetivos que guiaron la participación de militantes revolucionarios en las estructuras institucionales del Estado.Por otra parte, se analizan más específicamente las prácticas políticas desplegadas por estos militantes en el Ministerio de Asuntos Agrarios, junto a los programas de gestión impulsados, observando un repertorio heterogéneo de modalidades de acción inscriptas en un programa mayor de cambio de estructuras y construcción del socialismo nacional

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El episcopado de Gregorio Magno (590-604) representa un hito al momento de analizar el derrotero del cristianismo entre la Antigüedad Tardía y el Alto Medioevo. Hombre de enorme flexibilidad política y discursiva, construyó -a lo largo de su vida- un repertorio textual de incalculable valor para el historiador moderno. En una de sus obras de mayor impacto en los siglos posteriores -la Regula pastoralis- el obispo de Roma analiza minuciosamente el rol del hombre de Iglesia en todas sus facetas, realizando especial hincapié en la parénesis. El objetivo de este trabajo será comparar algunas de las directivas allí vertidas con el accionar efectivo de Gregorio, observable en el Registrum epistularum. Para lograr tal fin, nos concentraremos en las epístolas referidas al judaísmo en general y a los judíos en particular. Observaremos, de tal modo, la concordancia entre algunos de los lineamientos gregorianos establecidos en la Regula y su aplicación en el caso judío

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El desarrollo de la música electrónica en los últimos 20 años revela ambigüedades y tensiones del proceso cultural vivido por la sociedad argentina. El caso de la música electrónica, en tanto construcción de un espacio eminentemente multisensorial que modula una experiencia en la que dialogan articulaciones técnicas, sonoras y quími¬cas, junto ala centralidad del movimiento corporal, permite el encuentro, desarrollo y mutua redefinición de sexualidad y religión. Caracterizaremos ese encuentro posibilitado por la música electrónica como parte de la constitución renovada de las culturas juveniles. Por un lado describimos cómo el dispositivo de la música electrónica, dada la relevancia y trascendencia del baile, y dada la postulación de la unidad indisoluble entre cuerpo y mente, se articula con el sedimento cultural en el que opera la religiosidad de la Nueva Era. Por otro lado, pero en paralelo con lo anterior, mostra¬mos que el de la música electrónica es un espacio de interrogación y construcción de comportamientos sexuales en que el repertorio sexual se vuelve más plural que el definido por otras escenas musicales

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El presente artículo analiza, en líneas generales, el repertorio de las presentaciones de la recitadora cubana Eusebia Cosme entre 1934 y 1946, así como el diseño de los programas impresos de esas presentaciones. El propósito de este análisis es elucidar la importancia que ellas tuvieron en la constitución del canon de la moderna "poesía negra" hispanoamericana; investigar las motivaciones de los desplazamientos lexicales producidos en los atributos dados a esta poesía, e inquirir las razones de la persistencia, en el período, de las tensiones entre las categorías de "raza" y "cultura"

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Este artículo analiza el proceso de incorporación de los sectores de la Tendencia Revolucionaria del Peronismo en el gobierno de Oscar Bidegain en la provincia de Buenos Aires, a partir de las elecciones del 11 de marzo de 1973. Se busca analizar tanto la trayectoria previa de los grupos que integraron la administración provincial, sus lugares específicos en el organigrama gubernamental, junto con las expectativas, los sentidos y los objetivos que guiaron la participación de militantes revolucionarios en las estructuras institucionales del Estado.Por otra parte, se analizan más específicamente las prácticas políticas desplegadas por estos militantes en el Ministerio de Asuntos Agrarios, junto a los programas de gestión impulsados, observando un repertorio heterogéneo de modalidades de acción inscriptas en un programa mayor de cambio de estructuras y construcción del socialismo nacional.

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Dentro de las composiciones de extracción oral y popular se destaca la utilización de algunas palabras que entrañan una enorme significación. Se trata de estribillos que funcionan como una especie de muletilla expresiva, rítmica y metafórica, aunque el sentido oculto al que remiten resulte un tanto misterioso. Estos artilugios estilísticos, a mitad de camino entre la onomatopeya, el juego de palabras e ironías y el comodín rítmico y métrico, contienen muchas veces, un doble sentido insinuante que conlleva denotaciones pícaras y sensuales, atrevidas, procaces y a veces escandalosas. Este repertorio poético, antes desatendido, persiste no como reflejo pasivo de tradiciones heredadas, sino como crisol vivo de nuevas recreaciones y reconfiguraciones que impregnan géneros, repertorios y diversos registros

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Este artículo analiza el proceso de incorporación de los sectores de la Tendencia Revolucionaria del Peronismo en el gobierno de Oscar Bidegain en la provincia de Buenos Aires, a partir de las elecciones del 11 de marzo de 1973. Se busca analizar tanto la trayectoria previa de los grupos que integraron la administración provincial, sus lugares específicos en el organigrama gubernamental, junto con las expectativas, los sentidos y los objetivos que guiaron la participación de militantes revolucionarios en las estructuras institucionales del Estado.Por otra parte, se analizan más específicamente las prácticas políticas desplegadas por estos militantes en el Ministerio de Asuntos Agrarios, junto a los programas de gestión impulsados, observando un repertorio heterogéneo de modalidades de acción inscriptas en un programa mayor de cambio de estructuras y construcción del socialismo nacional

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El episcopado de Gregorio Magno (590-604) representa un hito al momento de analizar el derrotero del cristianismo entre la Antigüedad Tardía y el Alto Medioevo. Hombre de enorme flexibilidad política y discursiva, construyó -a lo largo de su vida- un repertorio textual de incalculable valor para el historiador moderno. En una de sus obras de mayor impacto en los siglos posteriores -la Regula pastoralis- el obispo de Roma analiza minuciosamente el rol del hombre de Iglesia en todas sus facetas, realizando especial hincapié en la parénesis. El objetivo de este trabajo será comparar algunas de las directivas allí vertidas con el accionar efectivo de Gregorio, observable en el Registrum epistularum. Para lograr tal fin, nos concentraremos en las epístolas referidas al judaísmo en general y a los judíos en particular. Observaremos, de tal modo, la concordancia entre algunos de los lineamientos gregorianos establecidos en la Regula y su aplicación en el caso judío